BUG #7632: Postgres binds to all IPs even when listen_addresses="localhost"

The following bug has been logged on the website:

Bug reference:      7632
Logged by:          Paul Jungwirth
Email address:      pj@illuminatedcomputing.com
PostgreSQL version: 9.1.6
Operating system:   Ubuntu 12.04 LTS, x86_64
Description:        =


After a default install of Postgres, I see that it's binding not just to
localhost, but also to my public IP. The port is reported open by nmap, and
I see this:

    # netstat -an | grep 5432
    tcp        0      0 66.175.223.51:5432      0.0.0.0:*              =

LISTEN     =

    tcp        0      0 127.0.0.1:5432          0.0.0.0:*              =

LISTEN     =


Postgres still binds to the public IP even after I uncomment the
`listen_addresses` line at `/etc/postgresql/9.1/main/postgresql.conf`, set
it to the following, and do `service postgresql restart`:

    listen_addresses =3D 'localhost'